by Fred E. Foldvary

If you sprawl on the floor, you spread your legs and arms out in an
uneven way. Urban sprawl is the excessive and scattered spreading
out of cities. Cities in the United States and elsewhere don't
grow gradually out in compact circles but extend helter skelter
here there and everywhere. This not only wastes good farmland and
wilderness, but increases the cost of city life and lead to urban
blight and congestion.

Think of a city doubling in population within the same area. The
density doubles, but the cost of providing services less than
doubles. The volume of piped water doubles, but the radius of a
pipe less than doubles because its area increases with the square
of the radius.

But if you keep the density the same and double the area, the cost
more than doubles. They have to put pipes in the new area, and
also increase the capacity of pipes in the center where the water
is pumped from.

Economist Mason Gaffney has divided urban policy into three types
with respect to sprawl. Negative containment tries to stop sprawl
by zoning it out. But if one area is closed to development, the
builders leapfrog over it to further out areas, making sprawl even
worse. Greenbelts and low-density zoning don't keep sprawl out,
but extend it further.

Neutral containment eliminates the subsidies to urban sprawl.
People living in the fringes of a city usually pay the same for
busses, water, sewers, gas, electricity, and streets as folks in
the city center. But, like the water example, utilities and
services don't just have to be extended to the new areas, but also
increased from the source of the service. Think of a one-inch pipe
of water from a house all the way to the pumps at the city center.

We use postage-stamp pricing for utilities, charging all users the
same no matter where they live or how much it costs. So the
residents and enterprises at the city center pay more than the cost
of serving them, and the folks in the edges of the city pay much
less than the cost of bringing them all those services. The
landowners at the fringes benefit because the subsidies pump up
their rents and land values.

Some cities have made developers pay an impact fee on new
developments, a cost which is passed on to the residents, which
reduces the subsidies. This is, however, quite an imperfect way of
paying for costs that continue indefinitely. Water, for example,
can be charged for in proportion to the distance the water has to
travel. If the price of living in the fringe gets too high, then
the city center will be more intensely developed instead.

We can go further than neutral containment to positive containment,
which makes the city a more attractive place to live and work.
This includes not just better transit, security, and other
services, but paying for public works from the land rent it
generates and eliminating all taxes on sales, buildings, and income
from wages and capital. The community collection of the rent would
eliminate the speculative profits from holding land out of its best
use, making city centers much more productive. The elimination of
taxes on improvements, profits, and wages would stop punishing
people from investing and working in the city.

People are not pushing the metropolitan border out just because
they like to live out in the fringes. Government is giving away
free money to those who want to sprawl out, and punishing those who
prefer to be in the city center. If we stop the sprawl subsidy and
have everyone pay his own way, then choices will reflect true
costs, and cities will become ever greater centers of civilization.